In a differential technology, a differential includes a driven gear of a final drive, a planetary gear, a center gear, and the like. The planetary gear is mounted on a secondary plate of the driven gear through a square shaft and a shaft sleeve and is meshed with the center gear, so as to implement revolution and moving functions thereof by a revolution pair and a planar moving pair. The center gear is connected to two half shafts, namely left and right half shafts, through an angular alignment pin and a cylindrical pair or through a spline to achieve an objective of outputting torque. Original components, such as left and right housings and a planetary gear shaft of the differential, are omitted from the differential, and instead, the planetary gear is directly mounted on the secondary plate of the driven gear of the final drive by using the square shaft and the shaft sleeve, thereby effectively reducing a number of parts of the differential, simplifying the structure thereof, and reducing the weight thereof.
However, such a differential implements an inter-wheel speed differential by using a symmetrical angle gear structure, which is only a partial innovation for a conventional symmetrical angle gear differential and cannot really overcome disadvantages thereof. For example, an axial dimension of such a differential structure is excessively large, masses of the housing and the angle gear therein are big, and reliability thereof is relatively poor.